Comparison of minimally invasive surgery and open surgery following chemotherapy for cStage IVb gastric cancer: a multicenter retrospective cohort study

BACKGROUND: The standard treatment for stage IV gastric cancer (GC) is chemotherapy, but advances in systemic therapy have rendered curative surgery a viable option. However, the role of minimally invasive surgery (MIS) in this context remains unclear. This multicenter retrospective cohort study aimed to evaluate safety and effectiveness of MIS post-chemotherapy for patients with cStage IVb GC. METHODS: Patients with cStage IVb GC who underwent curative-intent MIS or open surgery post-chemotherapy at 19 institutions between 2011 and 2022 were reviewed. Propensity score-matching was performed to adjust for confounding variables. The primary outcome was postoperative complications. Secondary outcomes were perioperative outcomes and long-term survival. RESULTS: Among 237 eligible patients (MIS, 130; open surgery, 107), 64 matched pairs were analysed. The incidence of Clavien-Dindo grade ≥ II complications was 31.2% in the MIS group and 46.9% in the open group, with no significant difference (risk ratio 0.67, 95% confidence interval [CI] 0.41-1.08). MIS was associated with a longer operative time (mean difference [MD] 98 min, 95% CI 53-143) but reduced blood loss (MD, - 550 g; 95% CI, - 738 to - 362). The MIS group achieved R0 resections more often (92% vs. 78%). The 3-year overall survival rates were 56.5% and 44.6%, respectively (hazard ratio 0.83, 95% CI 0.51-1.36). CONCLUSIONS: In curative-intent gastrectomy following chemotherapy for cStage IVb gastric cancer, MIS was not associated with worse perioperative outcomes or long-term survival compared with open surgery. Given its less invasive nature, MIS could be considered a feasible option for these patients when performed by experienced surgeons.